Rolling mill



J. J. OBRIEN ROLLING MILL July 21, 1931.

Filed Aug. 27, 1929 Patented July 2 1, 1931 PATENT oI-nca- I JEREMIAH J. O'BRIEN, F PITTSBURGH, PENNSYLVANIA.

ROLLING KILL Application fled August :7, 1929. Serial no. 888,710.

My invention relates broadly to certain new anduseful improvements in rolling mills, but more particularly to the novel process of manufacturing metal plates or sheets 5 by pressin the latter through successive pairs of re uction rolls, every alternate pair of which comprises rolls that are disposed and operated in non-parallel relation with res ect to each other.

' mportant objects of the invention are to provide a plate or sheet rolling mill structure and operation of the character described, which will facilitate and expedite the manufacture of metal plates 01' sheets; which will permit of the manufacture of plates or sheets of comparatively greater widths, of -unlimit-. ed lengths, and of uniform thicknesses which necessitates but slight mills already erected;' which embodies a novel straightener side-guard for conducting the plate or sheet into each stand of rolls, and for controlling its passage through the latter; and generally, which will simplify and improve the present rolling mill practice in regard to the method of obtaining plates or sheets that are erfectly straig t with parallel edges of uni orm thicknesses, and of unlimited lengths a-feature impossible in the present method of rolling sheet material.

Further objects of the invention are to provide a rollin mill embodying novel features which will adapt the apparatus to better perform the functions required of it, which are simple in their construction and arrangement, which will manifest required; roll adjustments, which are durable and highly efiicient in their use, and comparatively mexpensive to manufacture, install and operate.

With the foregoing and other objects in view which will appear as the descript1on proceeds, the 1117611131011 resides in the novel process of manufacturing metal plates or sheets, the manner heremafter being described, and as shownin the accompanymg drawings, but it is to be understood that the latter is merely illustrative of an embodlment of apparatus for carrying out my improved process and that variations in the construction and arrangement of such apparatus may change in sheet rolling 1 vpair of rest bars.

be resorted to without departing from the spirit or sacrificing any advanta es of the invention, as defined in the appen ed claims.

In the drawings wherein like numerals of reference designate corresponding parts throughout the several views:

Flgure 1 is a diagrammatic top plan view of an embodiment of the apparatus for manufacturing metal plates or sheets in accordance with the present invention.

F1gure 2 is a transverse cross sectional view of one stand of rolls, illustrating the adaptation of the straightener side-guard therewith.

Figure 3 is a side view of an associated o5 non-parallel, pair of rolls, showing. their relative positions.

Figure 4 is a top plan view of an associated Figures 5 and 6, are, respectively, side and end views of filler members.

Figure 7 is an inner side view of a modified form of straightener side-guard.

Referring in detail to the drawings '1, 2, 3 and 4, respectively, denote four separate stands of rolls, each of which includes a pair of associated reduction rolls, indicated at 5 and 6, the roll 5 being adjustable relatively to and disposed directly above the lower roll (3. The stands of rolls 1, 2, 3 and 4 are of a conso struction now commonly employed in sheet rolling mill practice, and well known in the art to which the invention appertains.

In my improved process, the stands of rolls 1, 2, 3 and 4 are associated in pairs, the stands 85, of rolls 1 and 2, constituting one such associated pair, and the stands of rolls 3 and 4 constituting another associated pair; It will here be noted that while illustrating and describing the invention as embodying but two pairs of stands of rolls 1,2, and 3, 4, respectively, it will be obvious that any required number of such associated pair of stands of rolls may be successfully employed to best meet conditions found in practice. 06 The associated pair of rolls 5 and 6, of the stands 2 and 4, are disposed and. operate m parallel relation with respect to each other in the usual manner, but the associated rel 5?.

5 and 6, of the stands 1 and 3, are non-pa;-- mo allel, relatively to each other, the said rolls and 6 being adjusted so that the distance between the right side ends is less than the distance between the left side ends thereof.

A straightener side-guard 7 and a bell side guard8 are mounted in front of each of the stands of rolls 1, 2, 3 and 4. The side-guards 7 and 8 are carried by a pair of rest bars 9, which latter are fixed to the top of a pair of supporting beams 10 by means of bolts 11. The supporting beams 10 are fixed in position to the respective stands of rolls 1, 2, 3 and 4.

The rest bars 9 are provided with longitudinally extending slots 12 adapted for the passage of the bolts 13, which extend through and secure the respective ends of the side guards'7 and 8 to the rest bars 9. The provision of the slots 12 in the rest bars 9 permits of the independent lateral adjustment of the side-guards 7 and 8, relatively to each other on the rest bars 9 to adapt same to the width of the sheet to, be rolled. The bottom side of the side-guards 7 and 8 are formed with a pair of recesses 14:, which overlap and engage the top of the rest bars 9 for further securing the side guards 7 and 8 against longitudinal movement on the rest bars 9.

The side-guards 7 and 8 are locked against lateral displacement by a plurality of T- shaped filler members 12 which are mounted in the rest bar slots 12 on the outerside of the side-guards 7 and 8. The inner portions of the side-guards 7 and 8 are formed with curved tapering ends 17, to allow the latter to be positioned in close proximity to respectivc pairs of rolls 5 and 6, as clearly shown in Figure 2.

A straightener side-guard 7 is disposed on the left sides of the stands of rolls 1 and 3, and on the right side of the stands of rolls 2 and 4. A bell side-guard 8 is disposed on the right sides of the stands of rolls 1 and 3, and on the left sides of the stands of rolls 2 and 4. It will here be noted that side guards 7 and 8 are alternately reversed on successive stands of rolls 1, 2, 3 and 4.

The purpose of the side-guards 7 and 8, is to control and conduct the sheet15, being rolled, through the successive stands of rolls 1, 2, 3 and 4. The bell side-guards 8, curve outwardly towards their front ends, and merely serve to direct the sheet 15 through the rolls 5 and 6, of the stands of rolls 1, 2,

and 4.

The straightener side-guards 7, however. constitute one of the most important features of the present invention, and not only serve to direct the sheet 15 through thereduction rolls, but further function to=control the path of travel of the sheet 15, and for maintaining the edges of the latter in exact parallel relation to each other throughout its passage through the rolls 5 and 6 of the successive stands of rolls 1, 2, 3 and 4. The inner or working face of the straightener'side-guard 7 is perfectly straight with the exception of the rounded front end thereof to facilitate the initial engagement of the adjacent edge of the sheet 15 along the straight inner side of the straightener side-guard 7.

In practice, the operation of my improved plate or sheet rolling process is as follows In the first stand of rolls 1, the straightener side-guard 7 is on the left side of the rolls 5 and 6. The latter are non-parallel, so that the reduction on the left side of the sheet 15 is less than on the right side thereof, and the magnitude of this difference in reduction can be varied by adjustment to meet the existing conditions found in practice, in the various stages of reduction.

This greater reduction on the right side of the sheet 15 causes the latter to travel transversely across the rolls 5 and 6 of the stand 1 toward the left, which is the side of least resistance, and forces the sheet 15 against straightener side-guard 7 ofthe stand 1.

Such transverse travel of the sheet is accomplished instantly, as the clearance is very small. and during this time the sheet is elongating and forming a slight camber 16 to the left side thereof.

The sheet 15, on leaving the stand of rolls 1 is perfectly straight. regardless of its length, due to its constant adherence to the straight inner side of the straightener side-guard 7 of the stand 1, but is thicker on its left side than on its right side due, of course, to the relative non-parallel positions of the rolls 5 and 6 of the stand 1.

The rolls 5 and 6. of the next stand 2, are parallel. thus causing a greater reduction on the thicker or left side of the sheet than on the thinner or right side. The short camber 16 that has formed on the left side of the sheet. will strike and travel along the inner side of the bell side-guard 8. which is located on the left side of the stand 2.

The greater reduction on the left side of the sheet 15 again causes it to travel to the right transversely across the rolls 5 and 6 of the stand 2 until it engages the inner straight face of the straightener side-guard 7, of the stand 2, located on the right side of the latter. As the rolls 5 and 6, of the stand 2, are set exactly parallel the sheet delivered therefrom is restored to uniform thicknesses on the edges. and will be perfectly straight rcgardless of its length, due to its adherence to the straightener side-guard 7 of the stand 2, which is itself'perfectly straight.

The passage of the sheet 15 through the rolls 5 and 6, of the first pair of associated stands 1 and 2, in the manner stated, compl tes the first operation in the continuous reduction of the sheet. The second, and subsequent operations are merely repetitions of the first in passing the sheet 15 through the second stands of rolls 3 and 4, and other pairs of Stands of rolls, until the sheet 15 is reduced and delivered in its finished form.

It will be evident, that in my improved process, the stands of rolls are necessarily associated in pairs, the first stands of rolls of any pair having non-parallel rolls which roll a sheet which is thicker on one edge than on the other, while the second stand of rolls of an associated pair of stands has parallel rolls, which restores the uniformity of the edges of the sheet. I

The illustration of the passage of the sheet 15 through successive stands of rolls' 1, 2, 3 and 4:, as shown in-Figure 1, is somewhat exaggerated and pronounced to render the relative course of the sheet 15 readily discernible. In actual practice, however, no distortion is perceptible.

In the known method of sheet rolling mill practice, each pair of associated reduction rolls are disposed and operate in exact parallel relation to each other, and it is impossible to roll sheets of unlimited lengths by such arrangement, for if a camber is formed on the sheet, owing to lack of heat uniformity, at respective edge margins of the sheet, or for any other reason, the-edges of the sheet will not be parallel or of uniform thicknesses, and such irregularity becomes more pronounced at each passage of the sheet through successive reduction rolls. From such conditions, waste, imperfect production and size limitations inevitably result.

By my improved process, however, the sheet is reduced by alternately passing the latter through non-parallel rolls to provide a sheet of unequal thickness, and then through parallel rolls to restore the uniform thicknesses of the edge margins of-the sheet. Heat inequality will not affect this rolling process as theoperation of the rolls will act directy upon that portion of the sheet which offers the greatest resistance thereto. In other words, the action of non-parallel and of the parallel rolls are identical in that they exert greater reduction toward one edge. of the sheet than toward the other, the non-parallel rolls 'reducin the sheet toward one edge, and the paral e1 rolls reducing the sheet toward the other edge thereof, thus alternately reducing one side then the other.

Further, by alternating the positions of straightener side-guards 7 on successive stands of rolls, the slight camber, produced during the passage of the sheet through the non-parallel and parallel rolls, will cause the constant adherence of the edges of the sheet against the straight inner faces of respective straightener side-guards 7, thereby producing a sheet of unlimited length with exactly parallel and straight side edges.

In the usual method of sheet rolling it is somewhatdi'flicult for the operatorto-deten mine what particular stand of reduction rolls is responsible for inaccuracies 111 the sheet,

but in my improved process the evidenceof any inaccuracies is obvious by any variations from the proper adherence of the sheet in eachof the stand of rolls to the straight face of the straightener side-guard 7 The modified form of straightener sideguard 7, illustrated-in Figure 7, differs from the preferred form herein described, only in hat a. longitudinally extending move 18 is formed on the inner face thereo to serve as a passage for engaging the edge margin of the sheet to direct the latter through the reduction rolls. The groove 18 may be flared toward its front end, as shown, to facilitate the engagement of the sheet therein.

It will here be noted that the bell sideguards 8 may also be provided with lon 'tudinally extending grooves on their inner aces for the purpose above stated. Further, it is apparent that side guards may be successfully employed on both the front and rear of each stand of rolls, if desired. In the use of flared grooved side guards, however, on the front and rear of the stand of rolls, the flared grooves in the side guards of the front of the stand would, of cours'e,be disposed oppositely to the grooves in the side guards at the rear of the stand.

In sheet rolling operations, the continued passage of sheets through the rolls will eventually form shoulders on the latter at respective ends of the pass through which the sheets travel between the rolls during the rolling operation. While such shoulders are barely perceptible, they are sufliciently pronounced to crimp, fracture and otherwise distort the side edges of the sheet, when the latter is rolled over same, thereby necessitating shearing of the side edges and consequent waste.

Particularly in rolling thin sheets by the present method, the side edges thereof are invariably distorted when being rolled between the shoulders of associated rolls.

Such distortion of the side edges of the sheets can be entirely eliminated by mounting a pair of straightener side-guards 8 at the front of some or each stand of rolls. The straightener side-guards 8 are properly spaced from each other to establish the required clearances for the sheet to be rolled.

By adjusting the rolls, which in present practice is readily effected by power operated apparatus, the same may be set to non-parallel positions relatit'ely to each other, whereby the sheet will be deflected transversely against any. pro-determined straightener gideiguard 8, in the manner herein before set ort It'will be obvious. that by periodically changing the nonparallel relation of assoside-guards 8 and utwardl'y of the pass be tween the rolls, leaving the entire pass between the latter free from all shoulder interruptions. Under such conditions, the pass between the shoulders of associated rolls includes ample clearances for the sheet, and the side edges thereof will be free from distortion, as the same cannot be engaged by the shoulders during the rolling operation. Further the wear on the shoulders and the straightener side-guards 8 will be simultaneous and uniform, whereby the wear to these elements is reduced to a minimum.

The present invention provides a most eflicient process for manufacturing plates or sheets, and permits of the economic production of plates and sheets of greater widths, unlimited lengths, uniform edge thicknesses, and parallel side edges.

From the foregoing description, taken in connection with the accompanying drawings,

the advantages and operation, of my improved process for metal sheet manufacturing, will be readily apparent to those skilled in the artto which the inventionappertains,

and while describing the process together with structures permitting its adaptation thereto, it is to'be understood that variations in the process may be resorted to which come within the scope of the claims hereunto ap ended.

\ hat I claim is:

1. In a metal plate or sheet manufacturing process, the steps of reducing the plate or sheet which consists of passing the latter through successive stands of reduction rolls,

7 and operating the latter alternately to first reduce said plate or sheet toward one side edge thereof and then to restore the uniform thickness of said plate or sheet.

2. In a metal plate or sheet manufacturing process, the steps of passing the plate or sheet through successive stands of reduction rolls, which stands are associated in pairs, operating the reduction rolls in one of said pair of stands in non-parallel relation with respect to each other, and operating the reduction rolls in the other of said pair of stands in parallel relation to each other. 7

3. In a metal plate or sheet manufacturing process, the steps of passing the plate or sheet through successive stands of reduction rolls which stands are associated in pairs, operating the reduction rolls in the first of said pair of stands in non-parallel relation with respect to each other, and operating the reduction rolls in the second of said pair of stands in parallel relation to each other.

4. In a metal plate or sheet manufacturing process, the steps of passing the plate or sheet through successive stands of reduction rolls which stands are associated in pairs, operatingthe reduction rolls in the first of said pair of stands to reduce the plate or sheet to less thicknesses toward one side edge than toward the other side edge thereof, and operating the reduction rolls of the second of said pair of stands to restore the uniformity of the thicknesses of both side edges of the plate or sheet.

5. In a metal plate or sheet manufacturing apparatus of the character described, a plurality of stands of cylindrical reduction rolls which are associated in pairs, the axes of the reduction rolls of the first of said pair of stands being disposed in non-parellel relation to each other, and the axes of the reduction rolls of the second of said pair of stands being disposed in parallel relation to each other.

6. In a metal plate or sheet manufacturing apparatus of the character described, a plurality of stands of cylindrical reduction rolls which are associated in pairs, the axes of the reduction rolls of the first of said pair of stands being disposed in non-parallel relation to each other, and the axes of the reduction rolls of the second of said pair of stands being disposed in parallel relation to each other, a pair of side-guards disposed at the front of each of said stands of reduction rolls, and means for supporting said pair of side-guards.

7. In a metal plate or sheet manufacturing apparatus of the character described, a plurality of stands of cylindrical reduction rolls which are associated in pairs, the axes of the reduction rolls of the first of said pair of stands being disposed in non-parallel relation to each other, and the axes of the reduction rolls of the second of said pair of stands being disposed in parallel relation to each other, a pair of side-guards disposed at the front of each of said stands of reduc tion rolls, and means for supporting said pair of side-guards, saidside-guards being adjustable relatively to each other.

8. In a metal plate or sheet manufacturing apparatus of the'character descri a plurality of stands of cylindrical reduction rolls which are associated in pairs, the axes of the reduction rolls pf'the first of said pair of stands being disposed in non-parallel relation to each other, and the axes of the reduction rolls of the second of said pair of stands being disposed in parallel relation to each other, a pair of adjustable side-guards disposed at the front of each of said stands of reduction rolls, and means for supporting i of stands being disposed in nonparallel rellti . lation to each other for reducing the plat'e or sheet to less thickness toward one side edge than toward the other side thereof, the axes of the reduction rolls of the second of said pair of stands being disposed in parallel relation to each other for restoring the uniformity of the thicknesses of both side edges of the plate or sheet and means being disposed at the front-oi: reduction \rolls for maintaining the side edges of the plate or sheet straight, and parallel to each other on the passage of the latteil'lsthrough successive stands of reduction ro 10. In a metal plate or sheet manufacturing apparatus of the character described, a plurality of stands of cylindrical reduction rolls, which are associated in pairs, the axes of the reduction rolls of the first of said pair of stands being disposed in non-parallel relation to each other for reducing the plate or sheet to less thickness toward one side edge than toward the other side thereof, the axes of the reduction rolls of the second of said pair of stands being disposed in parallel relation to each other for restoring the uniformity of the thicknesses of both side edges of the plate orsheet, and a straightener sideguard adjustably mounted at the front of each of said stands of reduction rolls, said straightener side-guards being alternately disposed on opposite sides of successive stands of reduction rolls and engaging respective side. edges of the plate or sheet for maintaining the same straight and parallel to each other during the travel of the plate or sheet through successive stands of reduction rolls.

11. In a metal plate or sheet manufacturing apparatus of the'character described, a plurality of stands of cylindrical reduction rolls, which are associated in pairs, the axes of the reduction rolls of the first-of said pair of stands being disposed in non-parallel rela-. tion to each other for reducing the plate or sheet to less thickness toward one side edge than toward the other side thereof, the axes of the reduction rolls of the second of said air of stands being disposed in parallel reation to each other forrestoringthe uniformity of the thicknesses of both side edges of the plate or sheet, rest bars, means carried by said stands of reduction rolls for supportin said rest bars, a straightener side-guard ad]ustably mounted on said rest bars and (115- posed at the front of, each of said stand of reduction rolls, said straightener side-guards being alternately disposed on opposite s1des of successive stands of reduction rolls and engaging respective side edges of the plateor sheet for maintaining the same straight and parallel to each other during the travel of the plate or sheet through successive stands I of reduction rolls.

12. Ina metal plate or sheetamanufactiir- I ing apparatus ofthe character described, a

each of saidstands of plurality of stands of cylindrical reduction rolls, which are associated in pairs, the axes of the reduction rolls of the first of said pair of stands being disposed in non-parallel relation to each other for reducing the plate or sheet to less thickness toward one side edge than toward the other side thereof, the axes of the reduction rolls of the second of said pair of stands being disposed in parallel reation to each other for restoring the uniofthe plate or sheet, a straightener si eguard adjustably mounted at the front of each of said stands of reduction rolls, said straightener side-guards being alternately disposed on opposite sides of successive stands of reduction rolls and engaging respective side edges of the plate or sheet for maintainstands being disposed in non-parallel relation to each other'for reducing the plate or sheet to less thickness toward one side edge than toward the other side thereof, the axes ofthe reduction rolls of the second of said pair of stands being disposed in parallel re lation to each other for restoring the uniformity of the thicknesses of both side edges of the. plate or sheet, restbars, means carried by said stands of reduction rolls for supporting said rest bars, a straightener side-guard ad ustably mounted on said rest bars and disposed at the front of each of said stand of reduction rolls, said straightener side-guards being alternately disposed on opposite sides of successive stands of reduction rolls and engaging respective side edges of the plate or sheet for maintaining the same straight and parallel to each other during the travel of the plate or sheet through successive stands of reduction rolls, and means removably mounted in said rest bars for locking said straightener side-guard against lateral displacement on said rest bars.

. 14. In a metal plate or sheet manufacturing ap aratus of the character described, a plura ty of stands of cylindrical reduction rolls,

' which are associated in pairs, the axes'of the reduction rolls of the first of -said pairof stands beingdisposed in non-parallel relation to each other for reducing the plate or sheet to less thickness toward one side edge than toward the other side thereof, the axes ice formity of the thicknesses of both side ed es 7 of the plate or sheet, and a straightener sideguard adjustably mounted at the front of each of said stands of reduction rolls, said straightener side-guards being alternately disposed on opposite sides of successive stands of reduction rolls and engaging respective sides edges of the plateor sheet for maintaining the same straight and parallel to each other during the travel of the plate or sheet through successive stands of, reduction .rolls, the inner face of each of said straightener side-guards being provided with a longitudinally extending groove for the reception of the adjacent edge of the plate or sheet. i

15. In a metal sheet rolling apparatus including a pair of rolls, a side guard disposed. adjacent to said pair of rolls, said side guide being formed with a longitudinally extending passage on the inner face'thereof for dis recting the sheet, through said pair of rolls.

16. In a metal sheet rolling apparatus including a pair of rolls, a side guard disposed adjacent to said pair of rolls, said side guide being formed with a longitudinally extending passage'on the inner face thereof for di-' recting the sheet through said pair ofirolls, said passage being flared toward one end thereof.

v 17. In a metal sheet rolling apparatus including a pair of rolls, a side guard adjustably mounted adjacent to said pair of rolls, said side guide being formed with a longitudinally extending passage on the inner face thereof for directing the sheet through said pair of rolls, said passage being fiared'toward one end thereof. I

18. In a metal plate or sheet manufacturing process, the steps of passing the plate or sheet through successive stands of reduction rolls provided with straightener elements, op-

erating every alternate stand of reduction rolls to reduce the plate or sheet to less thicknes's toward one side edge than toward the other side edge thereof and to force the thicker of said edges against and along the straightener element of the successive stand of reduction rolls, and operating the other of said stands of reduction rolls to restore the uniformity of the thickness of the plate or sheet and to force the said-previously reduced side edge or" the latter against and 7 along the straightener element of the successive stand of reduction rolls.

19. In a metal sheet manufacturing process, the steps of passing the sheet through successive stands of reduction rolls, rovided with straightener side-guards,'per1odically adjusting said stands of reduction rolls to effect a greaterredu'ction of the sheet toward one side edge than toward the otherside edge I thereof to force one side edge of the sheet against and along either of the straightener side-guards of the successive stand of reduction rolls for preventing the formation of 

